Zirconium pigments



Patented Jan. 20, 195 3 ZIRCONIUM PIGMENTS Warren Barnett Blumenthal, Niagara Falls, N. Y.,

assignor to National Lead Company, New York, I N. Y., a corporation of New Jersey No Drawing. Application March 15, 1950, Serial No. 149,903

Claims. (01. 260-147) The present invention relates to a new class of color pigments, and particularly to zirconium compounds of soluble acid dyestuffs, of distinctive chemical structure.

This application is a continuation-in-part of Serial No. 649,754, filed February 23, 1946, now abandoned. In U. S. Patent No. 2,492,959, granted January 3, 1950, I have described the reaction of hydrous zirconia hydro gels with basic dyes with the formation of pigments.

The addition of inorganic constituents to an organic dyestufi to produce a pigment possesses certain well known advantages and also well defined limitations. Generally, the inorganic constituents have been employed either as extend-.

ers or as substrates upon which coloring principles have been absorbed or precipitated. Also, an inorganic constituent is used as a precipitating agent to fix the dye upon the lake substrate.

Color lakes are defined as insoluble compounds produced by the absorption or precipitation of a coloring principle on an inert and insoluble base. Toners are organic pigments containing no inorganic pigments or inorganic carrying bases. In the precipitation of metallic lakes and toners, the metallic salts which are commonly used include those of barium, calcium, aluminum, tungsten, molybdenum, lead, tin and strontium. A typical manufacturing procedure is to add an aqueous solution of barium and aluminum chlorides to a slurry of alumina hydrate and an acid dyestufi. The dyestufi is precipitated practically quantitatively onto the alumina hydrate, forming a lake pigment. Acid dyes are organic coloring agents in which the dye-base takes the place of the acid constituent of a salt. In the lake-making art, acid dyes in common use are generally soluble coloring agents containing one or more carboxylic or sulr'onic acid groups or both. Lake pigments of this type find a wide application in the manufacture of printing inks, cosmetics and other color compositions. In such a lake composition, the function of the barium and aluminum salts is not to form insoluble compounds with dyestuff for, in general, the barium and aluminum compounds of acid dyestuffs are not insoluble materials. Their action is to impart adsorptive qualities to the substrate, viz., the alumina hydrate. While the alumina hydrate lakes in common use have been widely accepted as valuable coloring agents, they have some peculiar limitations: The substrate acts as a diluent and limits the color strength which can be developed from any dyestufi more- N stufi are precipitated onto a substrate, the lake will often bleed into water; furthermore, the

surplus dyestufi may have no value in increasing the color strength of the lake.

In accordance with the principles of the present invention, water soluble acid dyestufis, that is, dyestufi's containing one or more carboxyl or sulfonic acid groups, are caused to react chemically in highly acidic solutions with a water soluble salt of zirconium such as the oxychloride, oxynitrate and the like, i. e. the zirconyl salts, with the production of intensely colored, insoluble, non-bleeding pigments which are basic zirconyl salts in which the coloring principle of the dye acts as a colored anion. This chemical characteristic of formation of colored, insoluble, non-bleeding pigments formed as the reaction product of soluble zirconium salts and acid dyestulis, distinguishes zirconium salts from the case where soluble salts of other metals are used as inorganic additions in the usual productionof lakes and toners. For. example, the toners of most acid dyes cannot be made with aluminum salts. When these toners can be made, they are neither insoluble nor non-bleeding.

In accordance with the present invention, the use of zirconium salts which are highly acidic in water solution in pigment-making yields unique products in that the zirconium forms insoluble compounds with the dyestufi, or" definite chemical compositions, andofiering advantages to be described. Other metals do not react chemically to form insoluble compounds with acid dyestuiIs. By the novel action of salts of zirconium in acidic solution, which eliminates the substrate as an essential constituent of pigment compositions of acid dyes, the maximum color strengths of dyestuffs are rea1ized,.and greater freedom is attained for the use of a wide range of physical and chemical conditions of precipitating the coloring matter, for substrates frequently impose 'classes whether they be nitro or nitroso dyestuffs, azo dyestuffs, diazo dyestufis,'phenylmeth ane 'dyestufis, dyestuffs of the az ine, indamine,

xan-thane, thiazole, quinoline, hydroxyketone or other type of dye provided only that the dyestuff be an acid dye, that is, contain one or more carboxyl groups or sulfonic acid groups.

Although any zirconium salt capable of yielding a zirconyl radica1 or ion on hydrolysis and therefore highly acidic in aqueous solution, is suitable for use in manufacturing the insoluble, highly colored zirconium pigments, the zirconium oxychloride of commerce, because of its low cost, relatively high solubility and convenient basicity. is preferred to other water soluble zirconium salts. In general, it may be considered that the acid dyes comprise an organic coloring agentin which the dye base takes the placeof the acid-constituent of a salt; that is, that there is probablypres ent in solution a colored dye radical corresponding to an ion of negative charge capable of combining by double decomposition with the zirconyl cation of the water soluble zirconium salt. 'Whenever reaction occurs with a dye containing a car- 'boxyl group or a-sulfonic acid gro p, h y colored-dye'radical is'precipitated asa salt of the zirconyl radical.

The following is a-partial listof such dyes and the molecular ratios in which they react with zirconyl salts. Allof the compounds are basic-zirconyl-'saltsy'that is, salts containing" one or more Zr203++ radicals. They may also contain the radical 'ZrO++,and--some'dyes form two compounds with-zirconium containing different proportions ofZrzOs+ and ZrO++ radicals.

' Mgarplhliact- Color g 10 Dye I Y ofZr (as Indexho. Zrooh) with Dyestufi 1. Amaranth v.1184 :2. 2. Acid Green L 666 5:3. 3. Eosin 768 4:5. 4. Ericglaucine 671 3:1, also 5:2.

5. Fast Lt. Yellow 3G w 636 1:1. 6. Orange II 151 1:1, also 1:2. 7. Ponceau 2R 79 1:2. 8. Quinoline Yellow S 801 3:2. 9. Tartrazine 640 5:2. 10. Uran'me 766 1:2.

Although most of the examples given below employ ZrOCl'2.8H2O,' the zirconium oxychloride, as

the source of zirconium, it will be understood that the invention is'not restricted thereto since the following examples'are'merely illustrative'of the principles of invention rather than 'limitative thereof Example I lbs. or Add Green (Color Index No. 666) is dissolved in 70galsl 0f'waterat 122 F. Into this is run slowly a'solution containing '15 lbs. of zirconium oxychloride'in"20 gals. of water and possessing apH of 'I'to 1.5. The pH of the slurry is raised from a'pH of about 1 to a'pH of about 3.5 with sodium hydroxideand the slurry is stirred ten minutes and filtered.

V V M H The precipitate 'is washed and dried. Anintense green toner is obtained having a soft texture and useful pigment "lbs. of zirconium oxychlor'idein' gals of water. The slurry, at a pI-I' adjusted upwardly about 3.5

is stirred 10 minutesand filtered. The precipitate is'was'hed and dried. A yellowto ne r of high Example III In place of the Fast Light Yellow 3G of Exam ple II, use an equal weight of Tartrazine Yellow (Color Index No. 640). Before filtering, the pH is raised to about 3.5 and an emulsion of 10.3 gm.

of 00 lithographic varnish in 10.3 lbs. of water,

using 0.343 1b. sodium oleate as an emulsifying "agent'is added. After stirring for a short time,

filter, wash and dry the precipitate. A dry color is obtained of soft texture and high strength and brilliance. The color compound is apparently ""The reaction occurs generally with acid dyes andthe following are typical:

Erioglaucine 671) S Ii G Q eHrNczHscHeceHis a e) 2 "o an e II (4i"151),Nao 'sCgHiNgC HwH Quinoline Yellow (disulfonate) 1:]: 800) c 'hcaoz cnN- e.( S 03553. 2

Alizarine Cyanine G Extra (#lO78),--Ce H2eNeO S Na Alizarine Red S (#1034), C H O7SNa.H O

CzeHllNumS Na The products of the present invention can also be preparedin the presence of emulsified agents to enhance the tinctorialstrength as, for instance, using oleic acid emulsions as follows:

Example IV lbsI "Tartra'zin' Yellow is dissolved in "70 gals. of water at1 22" F.: 1.2 lbs. of 'oleic acid is emulsif ed in 10 gals. ofwater using 0.12' lb. of triethanolalnineias'an emulsifying agent. The emulsion is added slowly to theTartrazine'Yellow solution, simultaneous with the additionof asolu ,tion of 15lbs. of zirconiumoxychlori'de in 20 gals.

of water. The mix,a t an adjusted pI-I of below 3.5, is stirred briefiy and filtered, and the prec'ipitate is washed and dried. A" yellow toner is obtained of considerably higher tinctorial strength than 'if no emulsion is used.

above zirconyl compoiii'idsof acid dyes may be used as toners as they are organic pigments 'fcontai'riing no; merganle'plgmems or inorganic c'arryingba'ses or may'be'prepared as lakes, i.e., insoluble compounds produced by the absorption r p ci i a iq p c d ine p in p n en li and insoluble base. As; an example, the zirconyl salt of the dye may be prepared and absorbed on the lake base as, for instance, aluminum hydroxide or prepared in the presence of the inert base. A lake may be prepared asfollowsi Example V 12.3 lbs. of Tartrazine Yellow is'dissolved in '14 gals. of water and run slowly into alfilbsaof zirconium oxychloride which has been'dissolved in 60 gals. of water at 122 F. producing asolution of the dy'e'pigment in 'amounts -and at arate suificient' to maintain the "pH 'of the reaction environment at a"'constant"and 'low level;'='always lower than pH 3. 'I l'ie'ifollowin'g example illustrates this phase-of the-invention.

A solution of 120 grams'of Erioglaucine (Color Index 671) in 4000 cc. of water was treated with sufficient hydrochloric acid to produce a pH of 2.8. To this was slowly added 3200 cc. of an aqueous solution containing 330 grams of zirconium oxychloride (ZrOClaBHzO) the pH of which had been raised to 2.55 by addition of sodium carbonate (65 g. NazCOa in 300 cc. water). The temperature of the reacting solutions and resulting slurry was maintained at about 95 C. The addition was made over a period of about minutes and the pH in the slurry during addition was maintained at pH 2.8 by small increments of a dilute caustic soda solution or other alkali. Upon completion of the reaction, the slurry was stirred an additional 5 minutes at 95 C., then chilled to 50 C. by addition of cold water adjusted to a pH of 2.8 with HCl, filtered and Washed. A yield of about 265 grams of dye pigment was obtained the Erioglaucine content of which was approximately 45%.

The zirconium dye compounds are quite stable, and are equal to or better than alumina hydrate pigments in resisting the destructive agencies of light, soap and alkali, and the solvent action of water, alcohol and oleaginous vehicles. The zirconium dye compounds are useful as pigment toners, but may also be precipitated in the presence of substrates, forming lakes having valuable pigment properties.

In certain of the examples above, dispersing or coating agents are employed in addition to the dye and soluble zirconium salt in order to enhance the tinctorial strength and produce the desirable qualities associated with the employment of such emulsions.

The zirconyl and basic zirconyl derivatives of the acid dyes are useful as toner because of their stability, insolubility, non-bleeding characteristics, and because they are soft, easily ground, easily flushed compounds containing no substrate.

It will be understood that the term "zircony applies to the radical ZrO++ derived from the oxysalts, such as zirconium oxychloride, as for instance the so-called zirconium oxychloride of commerce, ZIOClaSI-IzO.

-What is claimed is:

The method of making a dye pigment from a water. soluble acid dye containing an acid group selected from acid groups consisting of carboxalate and sulfonate and a water soluble zirconium saltwhich comprises combining the dye in aque- 1 'tion with sufficient of a water soluble salt; at a pH of less than 3 whereby the ipitated as, a water insoluble compound the basiczirconyl radical of the "soluble 'zirconyl salt -in the pres'cnc i= 2'; The method "or making a dye pigment-from a water soluble acid idye i containing Jan; acid group selected from acid groups .consistingfiofi'carbox'alate andsulfonateand a water solubleizirconium salt which -comprisesmombining: the dye in aqueous solution with sufiicient: zirconyl: chloride at a pH of less than 3 whereby thedye" is precipitated as a water. insoluble :compound 0f the dye and the basic zirconyl radicalof the' i zirconium-salt.

Y 3. 'The' method of making. adye- -pigment from a water soluble acid d'ye 1 containing san'vacid group selected from acid 'groups consisting's: of 'c"arbox'alate and sulfonate and a-waterxsoluble'zir- "conium salt" which comprises combining :the dye in aqueous solution with "'suiiicien water H hydrochloric acid-sufficient to produceia pHbiiiess than 3' whereby the dyeis precipitated as a waterinsoluble compound" of the dye' and-thebasic zirconyl radical of the zirconium salt.

4. The method of making a dye pigment from a water soluble acid dye containing an acid group selected from acid groups consisting of carboxalate and sulfonate and a water soluble zirconium salt which comprises combining the dye in aqueous solution with sufiicient of a water soluble zirconyl salt at a pH of less than 3 whereby the dye is precipitated as a water insoluble compound of the dye and the basic zirconyl radical of the zirconium salt and separating the dye pigment from the solution.

5. The method of making a dye pigment from a water soluble acid dye containing an acid group selected from acid groups consisting of carboxalate and sulfonate and a water soluble zirconium salt which comprises combining the dye in aqueous solution with sufficient of a water soluble zirconyl salt at a pH of less than 3 whereby the dye is precipitated as a water insoluble compound of the dye and the basic zirconyl radical of the zirconium salt, raising the pH of the reaction mass to about 3.5 and separating the dye pigment.

6. The method of making a dye pigment from a water soluble acid dye containing an acid group selected from acid groups consisting of carboxalate and sulfonate and a water soluble zirconyl salt which comprises mixing an aqueous solution of the dye with sufficient of an aqueous solution of a water soluble zirconyl salt whereby the dye is precipitated as a water insoluble compound of the dye and the basic zirconyl radical and continuously adding alkali to the reaction mixture during the reaction to maintain a relatively constant pH in the mixture and at a level below pH 3.

7. The method of making a dye pigment from a water soluble acid dye containing an acid group selected from acid groups consisting of carboxalate and sulfonate and a water soluble zirconyl salt which comprises mixing an aqueous solution of the dye with sufficient of an aqueous solution of a water soluble zirconyl salt whereby the dye is precipitated as a water insoluble compound of the dye and the basic zirconyl radical and continuously adding alkali to the reaction mixture during the reaction to maintain a relatively constant pH in the mixture and at a level below pH 3 and then removing the dye pigment.

8. The method of making a dye pigment from a water soluble acid dye containing an acid group selected from acid groups consisting of carboxalate and sulfonate and zirconyl chloride which comprises mixing an aqueous solution of the dye with sufficient of an aqueous solution of zirconyl chloride to precipitate the dye as a water insoluble compound of the dye and the basic zirconyl radical and continuously adding alkali to the reaction mixture during the reaction to maintain a relatively constant pH in the mixture and at a level below pH 3.

9. The method of making a dye pigment from a water soluble acid dye containing an acid group selected from acid groups consisting of carboxalate and sulfonate and a water soluble zirconyl salt which comprises mixing an aqueous solution of the dye with sufficient of an aqueous solution of a water soluble zirconyl salt in the presence of hydrochloric acid whereby the dye is precipitated as a water insoluble compound of the dye and the basic zirconyl radical and continuously adding alkali to the reaction mixture during the reaction to maintain a, relatively con- REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,220,397 Crossley et al Nov. 5, 1940 2,259,736 Crossley et al. Oct. 21, 1941 2,492,959 Blumenthal Jan. 3, 1950 OTHER REFERENCES Georgievics et al.: Dye Chemistry, 1920,

stant pH in the mixture and at a level below pH 3. 20 pa e 2- 

10. A DYE PIGMENT COMPRISING THE WATER INSOLUBLE REACTION PRODUCT OF A WATER SOLUBLE ZIRCONYL SALT AND AN ACID DYE CONTAINING AN ACID GROUP SELECTED FROM THE ACID GROUP CONSISTING OF CARBOXALATE AND SULFONATE. 